error while trying the tutorial for restlet server

[Alessandro Debbia]

I was trying the tutorial for a restful web server using Restlet on Eclipse IDE, but i'm getting this error when i try to test it.

Exception while instantiating the target server resource.

java.lang.IllegalAccessException: class org.restlet.resource.Finder (in module org.restlet) cannot access class demo.DemoServer (in module provaRestlet) because module provaRestlet does not export demo to module org.restlet

at java.base/jdk.internal.reflect.Reflection.newIllegalAccessException(Reflection.java:361)

at java.base/jdk.internal.reflect.Reflection.ensureMemberAccess(Reflection.java:99)

at java.base/java.lang.Class.newInstance(Class.java:579)

at org.restlet/org.restlet.resource.Finder.create(Finder.java:148)

at org.restlet/org.restlet.resource.Finder.create(Finder.java:176)

at org.restlet/org.restlet.resource.Finder.find(Finder.java:193)

at org.restlet/org.restlet.resource.Finder.handle(Finder.java:219)

at org.restlet/org.restlet.Server.handle(Server.java:507)

at org.restlet.ext.nio/org.restlet.ext.nio.ServerConnectionHelper.handle(ServerConnectionHelper.java:252)

at org.restlet.ext.nio/org.restlet.ext.nio.ServerConnectionHelper.doHandleInbound(ServerConnectionHelper.java:181)

at org.restlet.ext.nio/org.restlet.ext.nio.BaseHelper$2.run(BaseHelper.java:585)

at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)

at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)

at java.base/java.lang.Thread.run(Thread.java:834)

No target resource was defined for this finder: Finder for DemoServer

How can i fix this??